Correlation of Infrasonic Microbarometric Disturbances and Long Period Seismic Phenomena
Abstract
Detailed analyses of the correlation of infrasonic microbarometric disturbances and long-period seismic phenomena as recorded at the high-gain, wide-band, long-period seismic observatory at Sugar Island, Michigan, show very low coherency in the range of periods between 10 and 120 sec. At periods greater than 60 sec, rising levels of microbarometric power generally correspond to rising levels of seismic 'noise' power indicating a genetic relationship. The lack of coherency between the data is attributed to the fact that a single point microbarometric measurement at the seismic recording site does not adequately represent the atmospheric loading of the earth's surface. To obtain high coherency, an array of weighted microbarometric measurements should be obtained in an area approximately 10 km in diameter around a broad-band, high- gain seismic receiver. A pronounced minimum in the seismic noise between 30 to 40 sec was observed in accordance with Savino's observations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1971
- Accession Number
- AD0728643
Entities
People
- Malcolm J. S. Johnston
- Paul W. Pomeroy
Organizations
- University of Michigan